• 제목/요약/키워드: Fisher's test

검색결과 814건 처리시간 0.028초

Combining Independent Permutation p-Values Associated with Multi-Sample Location Test Data

  • Um, Yonghwan
    • 한국컴퓨터정보학회논문지
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    • 제25권7호
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    • pp.175-182
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    • 2020
  • 연속형 분포로부터 얻은 독립적인 p값들을 통합하는 Fisher의 고전적인 방법은 널리 사용되고 있지만 이산형 확률분포로부터 얻은 p값들을 통합하기에는 적절하지 않다. 대신에 유사 Fisher의 통합방법이 이산형 확률분포의 p값들을 통합하는 대안으로 사용된다. 본 논문에서는 첫째, 여러 표본들의 위치검정(Fisher-Pitman 검정과 Kruskal-Wallis 검정) 데이터와 관련된 이산형 확률분포로 부터 퍼뮤테이션 방법에 의해 p값들을 구하고, 둘째로 이 p값들을 유사 Fisher의 통합방법을 이용하여 통합한다. 그리고 Fisher의 고전적인 방법과 유사 Fisher의 통합방법의 결과를 비교한다.

The Comparison of the Unconditional and Conditional Exact Power of Fisher's Exact Tes

  • Kang, Seung-Ho;Park, Yoon-Soo
    • 응용통계연구
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    • 제23권5호
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    • pp.883-890
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    • 2010
  • Since Fisher's exact test is conducted conditional on the observed value of the margin, there are two kinds of the exact power, the conditional and the unconditional exact power. The conditional exact power is computed at a given value of the margin whereas the unconditional exact power is calculated by incorporating the uncertainty of the margin. Although the sample size is determined based on the unconditional exact power, the actual power which Fisher's exact test has is the conditional power after the experiment is finished. This paper investigates differences between the conditional and unconditional exact power Fisher's exact test. We conclude that such discrepancy is a disadvantage of Fisher's exact test.

Combining Independent Permutation p Values Associated with Mann-Whitney Test Data

  • Um, Yonghwan
    • 한국컴퓨터정보학회논문지
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    • 제23권7호
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    • pp.99-104
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    • 2018
  • In this paper, we compare Fisher's continuous method with an exact discrete analog of Fisher's continuous method from permutation tests for combining p values. The discrete analog of Fisher's continuous method is known to be adequate for combining independent p values from discrete probability distributions. Also permutation tests are widely used as alternatives to conventional parametric tests since these tests are distribution-free, and yield discrete probability distributions and exact p values. In this paper, we obtain permutation p values from discrete probability distributions using Mann-Whitney test data sets (real data and hypothetical data) and combine p values by the exact discrete analog of Fisher's continuous method.

On Testing Fisher's Linear Discriminant Function When Covariance Matrices Are Unequal

  • Kim, Hea-Jung
    • Journal of the Korean Statistical Society
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    • 제22권2호
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    • pp.325-337
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    • 1993
  • This paper propose two test statistics which enable us to proceed the variable selection in Fisher's linear discriminant function for the case of heterogeneous discrimination with equal training sample size. Simultaneous confidence intervals associated with the test are also given. These are exact and approximate results. The latter is based upon an approximation of a linear sum of Wishart distributions with unequal scale matrices. Using simulated sampling experiments, powers of the two tests have been tabulated, and power comparisons have been made between them.

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평균과 비율 비교 (Hypothesis Testing: Means and Proportions)

  • 박선일;이영원
    • 한국임상수의학회지
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    • 제26권5호
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    • pp.401-407
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    • 2009
  • In the previous article in this series we introduced the basic concepts for statistical analysis. The present review introduces hypothesis testing for continuous and categorical data for readers of the veterinary science literature. For the analysis of continuous data, we explained t-test to compare a single mean with a hypothesized value and the difference between two means from two independent samples or between two means arising from paired samples. When the data are categorical variables, the $x^2$ test for association and homogeneity, Fisher's exact test and Yates' continuity correction for small samples, and test for trend, in which at least one of the variables is ordinal is described, together with the worked examples. McNemar test for correlated proportions is also discussed. The topics covered may provide a basic understanding of different approaches for analyzing clinical data.

수면 대장내시경 검진자에게 시행한 복부마사지의 효과 (The Effect of Abdominal Massage on Sleep Colonoscopy Subjects)

  • 이윤정;제남주
    • 한국산학기술학회논문지
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    • 제20권6호
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    • pp.410-420
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    • 2019
  • 본 연구는 수면 대장내시경 검진자에게 복부마사지를 시행하여 장운동 회복과 복부팽만감에 미치는 효과를 파악하기 위하여 시도된 비동등성 대조군 전후 시차설계연구이다. 연구대상자는 C시, G병원에서 외래를 통해 수면 대장내시경 검진을 받는 실험군 22명, 대조군 22명으로 자료 수집 기간은 2018년 6월 1일부터 8월 25일까지였으며, 실험의 확산효과를 막기 위하여 대조군을 먼저 자료수집 한 후 시차를 두고 실험을 실시하였다. 자료분석은 IBM SPSS 24.0을 이용하여 자료를 분석하였으며, 대상자의 일반적 특성의 동질성을 검증하기 위하여 독립표본 t-test, $x^2-test$ 와 Fisher's exact probability test, 실험군, 대조군의 복부둘레 변화량에 대한 정규성을 검증하기 위하여 Shapiro-Wilk로 검증, 복부둘레의 사전 동질성을 검증하기 위하여 Mann-Whitney U test를 실시하였다. 실험처치 효과 검증은 Fisher's exact probability test, Friedman test와 Mann-Whitney U test로 검증하였다. 연구 결과, 복부마사지가 대장내시경 검진자의 가스배출 시간($x^2=19.75$, p<.001)과 복부팽만감($x^2=29.93$, p<.001)을 감소시켜, 수면 대장내시경 검진자의 가스팽만으로 인한 불편감을 완화하는 간호중재로 활용할 수 있을 것으로 생각된다.

사상체질(四象體質)의 유전성(遺傳性) 검토(檢討)에 대한 통계적(統計的) 연구(硏究) (Statistical Study on Heredity in SaSang Constitutional Medicine)

  • 김대윤;이재원;김달래
    • 사상체질의학회지
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    • 제11권1호
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    • pp.159-168
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    • 1999
  • Purpose : Sasang Constitutional Medicine explains the pathology peculiar to constitution and suggests treatment for each constitution. In Sasang Constitutional Medicine hwnan beings are classified on four groups; Taeyangin, Taeumin, 5oyangin, Soeumin. These four constitution has their's own symptoms and treatments. In treatment, control of mind inclination, that is to say, moderation takes a very important role. But the study on heredity in Sasang Constitutional Medicine has not done not biological study but also statistical study. So we used several statistical methods and analyzed 163 samples. Methods : We implemented Fishers exact test for adjusting chi-squared test, kappa coefficient to estimate agreement of parent's and children's constitutions, and finally plotted bi-plot using correspondence analysis. Results : From Fisher's exact test result, we could know that parent's and children'S constitution's distribution had significant difference. In kappa coefficient, mother and daughter's estimated value produced highest result. In correspondence analysis we only plotted the case of mother and son for easy interpretation. Conclusion : In the study of heredity of SaSang constitution, we cannot know exactly the heredity of constitution in terms of biology or genetics. But this research can be helpful for further analysis, that is, a study of biological or genetical aspects. And we could conclude that in statistical aspects the heredity in SaSang constitution is meaningful.

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SOM을 이용한 LVQ 네트워크 설계 (LVQ Network Design using SOM)

  • 김영렬;이용구;손동설;강성호;엄기환
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2002년도 추계종합학술대회
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    • pp.382-385
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    • 2002
  • 본 연구에서는 LVQ의 성능 개선을 위하여 SOM을 전처리로 이용하여 LVQ 네트워크를 설계한다 제안한 설계 방법에선 SOM을 이용하여 LVQ 네트워크의 출력 뉴런 수와, reference vector의 초기값을 결정한다. SOM을 전처리로 이용한 LVQ를 Fisher의 Iris 데이터에 분류에 적용한 결과 기존의 LVQ보다 분류 성능이 뛰어났다.

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20세기 전반기 통계학사에 대한 연구 : 통계적 검정과 심리학을 중심으로 (A Study on the History of Statistics in the Early Twentieth Century Focused on Statistical Tests and Psychology)

  • 조재근
    • 한국수학사학회지
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    • 제26권4호
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    • pp.277-299
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    • 2013
  • It was not until the early twentieth century that statistics emerged as an independent academic discipline. The developments of statistical theory and methods would not have been possible without heated controversies among founding fathers. One of them, controversy on the statistical test between R. A. Fisher and J. Neyman, E. S. Pearson had been very fierce and long-lasting. On the other hand it was in the early twentieth century that psychologists began to utilize statistical test which was a hybrid of tests developed by Fisher and Neyman-Pearson. By considering the history of fields such as psychology, we can see distinctive characteristics specific to the history of statistics.